There is a range of power settings depending on departure airport altitude and outside air temp, but for a max power takeoff from at an airport elevation from sea level to 1000' engines 1&3 should be set to 2.10 EPR and engine 2 should be set at 2.12 EPR. This is on a non hushkitted JT8D-7/-9/-15 engine. This TO EPR setting is good up til 30C after 30C it drops off.

Climb EPR which is set after flap retraction is complete is dependant on altitude and temp. So an initial climb EPR seting of about 1.90 @ 3000 ft is a good rule of thumb.

In order to be accurate you will need the EPR charts. There are Max EPR takeoff charts and Reduced EPR takeoff charts. All settings are dependant on temp and altitude. The climb EPR should be set every 2000' according to temp and pressure. But thats' the engineers job.